Analysis of Juice Yield, Sugar Content, and Biomass Accumulation in Sorghum

Abstract

Because of its high potential for biomass production, adaptation to marginal conditions, and sugar‐rich stalks, sorghum [Sorghum bicolor (L.) Moench] has been recognized as a prospective source as biofuel feedstock. Tapping into this potential, however, requires development of distinct varieties and hybrids with enhanced value as feedstock source. The objectives of this study were (1) to determine the inheritance of key plant traits associated with biofuel production and (2) to identify new genetic sources that can be used in breeding programs to improve these traits. Six high‐biomass and/or sweet sorghum pollinator genotypes and three grain sorghum seed parents were intercrossed using the Design II mating scheme. The hybrids and their parents were evaluated in three environments in a randomized complete block design with three replications. Data were collected on plant height, days to flowering and maturity, biomass, juice yield, Brix, and lodging. General combining ability (GCA) for male parents was highly significant for all traits, and the top pollinators had 85, 34, and 47% higher juice yield, Brix, and biomass, respectively, compared with the overall mean of the hybrids. Specific combining ability effects were also significant but much lower than the variation revealed by GCA among males. Two of the males (PI257602 and PI185672) had the top scores for all traits considered and, hence, are excellent resources for breeding sorghum as biofuel feedstock.

Assessment of Stalk Properties to Predict Juice Yield in Sorghum

“…Photoinsensitive genotypes are preferred in breeding schemes since flowering in these materials occurs independently of day length; therefore, these ideotypes can and are used in breeding programs across several distinct environments. Significant genotypic variability was also observed in rather distinct populations consisting of various photoinsensitive and sensitive genotypes and environments [4,8,15,19,26,29,[36][37][38][39], demonstrating that improvement of these traits through genetic manipulation, especially by intercrossing photoinsensitive lines, is feasible in sorghum. Repeatability estimates were moderate to high for all traits, indicating that the phenotyping techniques employed in this study were relatively consistent.…”

Tapping the US Sweet Sorghum Collection to Identify Biofuel Germplasm

“…In the United States, the majority of ethanol production for bioenergy is from grain, mainly corn and to lesser extent, sorghum. Because these are food and feed grains, alternative sources are being evaluated (Godoy and Tesso 2013). Sweet sorghum is a source of easily fermentable sugars, produces large biomass, has a short growing cycle, is tolerant to drought, and capable of growing in marginal soils making it a desirable Flowering a 0.65*** 0.68*** 0.73*** 0.02 0.43*** n.a n.a Plant height b 0.45*** 0.71*** 0.76*** 0.13 0.39*** n.a n.a Fresh weight 0.43*** 0.77*** 0.86*** 0.07 0.21 n.a n.a Dry weight 0.40*** 0.72*** 0.82*** 0.21 0.64*** n.a n.a Brix 0.28* 0.17 0.25* 0.27* 0.38*** n.a n.a % moisture c -0.06 -0.14 -0.30** 0.25* 0.12 n.a n.a alternative bioenergy crop.…”

Sorghum stem aerenchyma formation is regulated by SbNAC_D during internode development

“…Sorghum stems have the capacity to accumulate high concentrations (~0.5 M) and large amounts of sucrose (up to 40% by weight) similar to sugarcane (Bihmidine, Hunter, Johns, Koch, & Braun, 2013;Godoy & Tesso, 2013;Gutjahr et al, 2013;Lingle, 1987; McKinley, Rooney, Wilkerson, & Mullet, 2016). Stem volume, juiciness, and sugar concentration have been under selection in sweet sorghum in order to maximize sugar yield (Burks, Kaiser, Hawkins, & Brown, 2015;Carvalho & Rooney, 2017;Murray et al, 2008).…”